Diandra Douglas says she fears for the mental health of her and Michael Douglas’ troubled son, Cameron, after he was sentenced to an additional 4 1/2 years in jail — with no family visits for two years — for possessing drugs in his cell.

Diandra continued, “I believe that solitary is only still practiced in the USA, as it has been proven not to help rehabilitate anyone, and only serves to make prisoners paranoid, anxiety ridden, etc. Humans — and certainly my son — are by their very nature in need of other human contact to maintain mental health.”

She said that they’ll appeal and that — like his father, who went into rehab in 1992 — Cameron should get treatment.

Diandra said, “We will appeal this sentence . . . It is way too harsh and unjust.

“I have not been allowed to see Cameron for the past two months or speak to him. My only communication has been through the mail. Cameron is fighting an addiction, which is a disease that runs in his family. Would you put a diabetic into solitary confinement in prison . . . to cure him?

“Two years with no family visitation, with only one call out per month. The hope and love that Cameron receives from his family visits, I believe, is what sustains him through these unbearable times . . . We boost his self- esteem, of which he has been totally robbed.”

While Michael was not present for Cameron’s Dec. 21 sentencing, Diandra left the court sobbing.

She added, “I make a point to show up for my son regardless of whether his father’s side of the family chooses to do so. When you have a child who is ill and afflicted with severe addiction, what they need is love, support and hope.”